KEGG   ENZYME: 4.99.1.7Help
Entry
EC 4.99.1.7                 Enzyme                                 

Name
phenylacetaldoxime dehydratase;
PAOx dehydratase;
arylacetaldoxime dehydratase;
OxdB;
(Z)-phenylacetaldehyde-oxime hydro-lyase
Class
Lyases;
Other lyases;
Sole sub-subclass for lyases that do not belong in the other subclasses
BRITE hierarchy
Sysname
(Z)-phenylacetaldehyde-oxime hydro-lyase (phenylacetonitrile-forming)
Reaction(IUBMB)
(Z)-phenylacetaldehyde oxime = phenylacetonitrile + H2O [RN:R07638]
Reaction(KEGG)
Substrate
(Z)-phenylacetaldehyde oxime [CPD:C16075]
Product
phenylacetonitrile [CPD:C16074];
H2O [CPD:C00001]
Comment
The enzyme from Bacillus sp. OxB-1 contains protoheme IX, the iron of which must be in the form iron(II) for activity. (Z)-Phenylacetaldoxime binds to ferric heme (the iron(III) form) via the oxygen atom whereas it binds to the active ferrous form via the nitrogen atom. In this way, the oxidation state of the heme controls the coordination stucture of the substrate---heme complex, which regulates enzyme activity [2]. The enzyme is active towards several (Z)-arylacetaldoximes and (E/Z)-alkylaldoximes as well as towards arylalkylaldoximes such as 3-phenylpropionaldoxime and 4-phenylbutyraldoxime. However, it is inactive with phenylacetaldoximes that have a substituent group at an alpha-site of an oxime group, for example, with (E/Z)-2-phenylpropionaldoxime and (E/Z)-mandelaldoxime. The activity of the enzyme is inhibited completely by the heavy-metal cations Cu+, Cu2+, Ag+ and Hg+ whereas Fe2+ and Sn2+ have an activatory effect.
History
EC 4.99.1.7 created 2005
Pathway
Cyanoamino acid metabolism
Styrene degradation
Microbial metabolism in diverse environments
Orthology
K10566  
phenylacetaldoxime dehydratase
Genes
BACO: 
Taxonomy
Reference
1  [PMID:10651646]
  Authors
Kato Y, Nakamura K, Sakiyama H, Mayhew SG, Asano Y.
  Title
Novel heme-containing lyase, phenylacetaldoxime dehydratase from Bacillus sp. strain OxB-1: purification, characterization, and molecular cloning of the gene.
  Journal
Biochemistry. 39 (2000) 800-9.
  Sequence
[baco:OXB_1097]
Reference
2  [PMID:15596434]
  Authors
Kobayashi K, Yoshioka S, Kato Y, Asano Y, Aono S.
  Title
Regulation of aldoxime dehydratase activity by redox-dependent change in the coordination structure of the aldoxime-heme complex.
  Journal
J. Biol. Chem. 280 (2005) 5486-90.
Other DBs
ExplorEnz - The Enzyme Database: 
IUBMB Enzyme Nomenclature: 
ExPASy - ENZYME nomenclature database: 
UM-BBD (Biocatalysis/Biodegradation Database): 
BRENDA, the Enzyme Database: 
CAS: 
203210-76-8

DBGET integrated database retrieval system